1. Field of the Invention
The invention relates to a holding device for body fluids, tissue parts and cultures.
2. Description of the Prior Art
From WO 93/22647 A1 a method and a device for separating a mixture of at least two media is known, in which the holding container is in the form of an approximately cylindrical or tubular housing with a container wall, which surrounds an inner space and the holding container has two end areas with open end sides respectively spaced apart from one another in the direction of its longitudinal medial axis. These two openings can be closed by if necessary openable closure devices, whereby one of which overlaps the holding container on its outer surface and the other closure device is designed such that the latter comprises a penetrable seal body and a holding element for the seal body, whereby the seal body is inserted into the inner space of the holding container and the holding element overlaps the holding container in the region of its outer surface. Furthermore, a separating device is inserted into the inner space of the holding container, which is designed by a main body with sealing lips projecting therefrom.
A holding container for centrifuging is known from U.S. Pat. No. 3,434,615 A, which is formed by a container body designed to be open at one end, which has a neck-like projection, whereby an inner surface of the neck-like projection is designed to taper conically in the direction of the inner space. In this conically designed neck region a diametrically opposed conically designed seal device in the form of a seal stopper with sealing rings arranged on the circumference can be used, whereby the seal stopper is held on the side of a flange of a cap relative to the housing opposite the inner space of the housing. In addition, between the cap and the housing a screw thread is arranged, with which the cap can be screwed into the housing or its neck-like projection. Because of the interaction of the seal stopper and the cap on the one hand and between the cap and the neck-like projection of the housing on the other hand, the seal stopper can be brought into a sealed position on the conical seal surface.
An additional holding device for blood is known from U.S. Pat. No. 3,897,343 A, in which the separating device is arranged before the insertion of the media to be separated in the region of the closed end side of the holding container. In the region of the open end face of the holding container a penetrable closure device is arranged, which is penetrated by a needle to insert the medium into the inner space of the holding device, and then the medium is introduced into the inner space. In this way the separating device before the commencement of the separating process is below the medium to be separated and only floats up after applying centrifugal force because of the selected specific weight to the separated and heavy components of the medium, and only after the end of loading by centrifugal force adopts a sealing position between the two separated components of the medium. A disadvantage of this known method or known device is that the separating device comes into contact with both components of the medium before the separating process begins, and it is thereby possible that partial amounts of the heavy medium stick in the region above the seal device on the separating device, and thus afterwards a mixing or polluting of the lighter medium above the separating device is possible after the completion of the separating process.
Furthermore, there is already known a holding device for the mixture of at least two media, according to DE-A1-19 513 453, which has a test-tube-like holding container, which is closed at an open end face area by a closure device, and in which there is inserted a separating device for holding apart the various media of the mixture after separation. In order to prevent the end face of the separating device, which subsequently comes into contact more with one medium, from being contaminated while the mixture is being filled into the inner space of the container, the separating device is provided in its central area with a through opening, through which the mixture can be introduced into the remaining inner space of the holding container. During the following separating procedure by centrifuging in a previously known way with a radial centrifugal force (rcf) of 1,000 g to 5,000 g, g being gravitational force and 1 g having a value of 9.81 m/s2, one of the media separated from the mixture is transferred through the aperture in a separating device into the area located between the seal device and the separating device and as a result sinks in the direction of the closed end of the holding container. In order to prevent the medium between the closed end and the separating device, after separation through the aperture, from mixing again with the medium separated therefrom, there is provided at a level corresponding to the normally remaining quantity of the other medium an end stop expanding conically in the direction of the closed end, by means of which the separating device impinges on the end stop which penetrates through the aperture. As soon as the outer diameter of the end stop corresponds to the inner diameter of the aperture, the separating device remains in this position, the aperture is closed by the stop, and no interchange or repeated admixture of the two media can take place. A disadvantage in this variant is that a special tube with an internally-located stop must be produced, and reliable separation of the media, due to the aperture located in the separating device, cannot be guaranteed.
Other holding devices for centrifuging mixtures to be separated consisting of at least two different media, in which the holding container is closed at both end face areas by a closure device, are known from WO-A1 96/05770. Located in the interior is a separating device in the form of a sealing disc, which is formed by a gel. During centrifuging this gel plug, due to its specific weight, which is higher than the specific weight of the medium with the lower specific weight, and is lower than the specific weight of the medium with the higher specific weight, migrates due to the centrifugal forces acting thereon between the two different media separated from one another. In this positioned location a separation of one medium from the other medium of the mixture can thus take place. A disadvantage here is that the storage time, due to the separating device made of gel, is in many cases insufficient for normal duration of use.
The object underlying the present invention is to provide a holding container, a holding device, and a method of separating a plurality of media of a mixture, which may be rapidly adapted to various mixtures, and enables a long storage period and a high degree of operational reliability, even when used by unskilled personnel.